Open Access Original Research Article

Quality and Quantity of Organic Fractions as Affected by Soil Depth in an Argiudoll under Till and No-till Systems

Juan A. Galantini, Matias Duval, Juan M. Martinez, Verónica Mora, Roberto Baigorri, José M. García-Mina

International Journal of Plant & Soil Science, Page 1-12
DOI: 10.9734/IJPSS/2016/25205

Aims: The aim of this study was to evaluate the long-term effect of tillage systems on the quantity and quality of organic carbon fractions at different soil layers.

Study Design: The experimental design was a split plot with three blocks. The long-term effects (25 years) of conventional- (CT) and no-tillage (NT) systems on a Tipic Argiudoll was sampled at 0-5, 5-10, 10-15 and 15-20 cm soil depth.

Place and Duration of Study: The field experiment was carried out at Tornquist (38° 07’ 06” S - 62°02’ 17” O) and soil sampling was performed during wheat seeding (June 2011).

Methodology: Total soil organic carbon (SOC) content and the following fractions were determined: Coarse particulate (POCc, 105-2000 µm), fine particulate (POCf, 53-105 µm) and mineral-associated (MOC, 0-53 µm) carbon fractions; humic (HA) and fulvic (FA) acids; and total (CHt) and soluble (CHs) carbohydrates. The main physico-chemical properties of HA and FA were analyzed using both FT-IR and fluorescence spectroscopies.

Results: After 25 years, total SOC at the 0-20 cm depth was 9% higher in no-tilled than in tilled soils. The POCwas the SOM fraction that turned out to be the most sensitive to tillage effects. The POCc:POCf:MOC ratio at 0-20 cm was similar for NT (3:14:82) and CT (5:10:84); however, differences were found across soil depths. Tilled soils showed higher aromaticity, starting by CH-degradation, in more superficial soil layers.

Conclusion: The no-tillage system presented a different pattern which can be related to distribution of crop residues and conditions for humification along the soil depth.

Open Access Original Research Article

Modeling of Soil Exchangeable Sodium Percentage Function to Soil Adsorption Ratio on Sandy Clay Loam Soil, Khartoum- Sudan

Mohammed M. A. Elbashier, Shao Xiaohou, Albashir A. S. Ali, Bashir H. Osman

International Journal of Plant & Soil Science, Page 1-6
DOI: 10.9734/IJPSS/2016/25389

An experiment was conducted at the Wadi Soba farm, Khartoum- Sudan. The aim of this study is to estimate the Exchangeable Sodium Percentage (ESP) function to Sodium Adsorption Ratio. In this study, linear regression model (ESP-SAR model) for predicting soil ESP from SAR was suggested. For this purpose, 30 soil samples were collected from the field of experiment, soil ESP was estimated from soil SAR in order to compare the predicted results with measured SAR using laboratory tests on saline and non- saline soil samples. The results show that on saline soil samples, the Standard Error of Mean (SEM) of predicted ESP obtained by ESP-SAR model was (0.9389) and the P-value was (0.0572). On non- saline soil samples, the Standard Error of Mean (SEM) of predicted ESP acquired by ESP-SAR model was (0.2920) and the P-value was (0.2628). The statistical results indicated that the linear regression model (ESP-SAR model), ESP= 0.84 × SAR + 2.17 with R= 0.7347 has a good performance in predicting soil ESP from SAR meanwhile the ESP-SAR model reflected more accuracy on non- saline soil samples and it can be recommended for both saline soil and non-saline soil samples.


Open Access Original Research Article

Phytoremediation Potential of Ricinus communis L. (Castor Oil Plant) in Northern Nigeria

Z. I. Yashim, E. B. Agbaji, C. E. Gimba, S. O. Idris

International Journal of Plant & Soil Science, Page 1-8
DOI: 10.9734/IJPSS/2016/21680

This research work is a field experiment carried out to evaluate the phytoremediation potential of Ricinus communis L (castor oil plant) in Zaria town of northern Nigeria. The sandy loam field (pH 6.78) used in the experiment was contaminated with Cd, Co, Ni and Pb from a metal dumpsite. A solution of 5 mmol/kg ethylenediamine-tetraacetic acid (EDTA) was applied on a portion of the field.  The harvested plant and the soil collected from the experimental and control sites were analysed using atomic absorption spectrophotometer to determine the concentrations of Cd, Co, Ni and Pb in different parts of the plant and the soil treated and untreated with EDTA. The physicochemical parameters of the soils - pH, moisture content, particle size, cation exchange capacity (CEC) and organic matter (OM) were determined. The concentrations of the metals in the different parts of the plant harvested from the experimental site were higher than those from the control soil. The statistical analysis using One-way ANOVA Duncan grouping, showed that there is a significant difference (P < 0.05) between the concentrations of the studied metals in the soil and that of the plant tissues at the dumpsite. Also the metal levels in plant harvested from the soil treated with EDTA were higher than those from untreated soil and the increases for the studied metals in the entire plant were by the following factors: Cd – 1.9, Co – 1.8, Cu – 1.5, Ni – 8.8, Pb – 2.1 and Zn – 1.4. The Bioaccumulation factor (BF) and Translocation factor (TF) for the metals studied varied. Ricinus communis L (castor oil plant) was found to have good phytoremediation potential for soil contaminated with heavy metals.


Open Access Original Research Article

Assessment of Soil Quality of Some Lands in Thanjavur and Tiruvarur Districts for Improved Cultivation of Rice and Sugarcane

M. Shanmuganathan, A. Rajendran

International Journal of Plant & Soil Science, Page 1-19
DOI: 10.9734/IJPSS/2016/24091

Soil quality is defined as the soil’s capacity to function within natural or managed ecosystem boundaries and to sustain plant productivity while reducing soil degradation. It can be assessed by selecting different indicators upon which the functions of soil depend. Researchers at Bishop Heber College, India have formulated a Soil Quality Index called after their names as Heber Soil Quality Index (HSQI) for the first time in India. In the present work, an attempt has been made to use the soil Heber Soil Quality Index (HSQI) to assess the suitability of a soil of a chosen area for the cultivation of rice and sugar cane. The quantity of soil quality parameters chosen in this study was determined using the proven methods given in the literature.The overall HSQI values of all samples ranged from 76.18 – 85.40, which reveals that the quality of soils studied in this investigation is good for the cultivation of rice and sugarcane. HSQI also provides the necessary information needed to maintain the optimum fertility year after year. It is a time saving and economically convenient process.


Open Access Original Research Article

Nutrient Release Patterns of Tithonia Compost and Poultry Manure in Three Dominant Soils in the Southern Guinea Savanna, Nigeria

G. O. Kolawole

International Journal of Plant & Soil Science, Page 1-8
DOI: 10.9734/IJPSS/2016/25828

Aim: Incubation experiment was conducted to determine nutrient release patterns of tithonia compost and poultry manure in three dominant soils in the southern Guinea savanna, Nigeria.

Study Design: Complete randomized design replicated three times.

Methodology: Two- kilogram surface soil (0-15 cm depth) each of the three dominant soils, (Itagunmodi (Rhodic Paleutult), Egbeda (Oxic Paleustult), and Majeroku (Abruptic Tropaqualf) was weighed into plastic pots, replicated three times and arranged in a completely randomized design. Tithonia diversifolia compost (tithonia) and poultry manure were applied at the rate of 5 tDM ha-1 to each pot as necessary. Pots without compost were included for comparison. The pots were covered with a double layer of 0.05 mm thick polyethylene film. At the end of 0, 7, 21, 28, 35 and 42 days, the incubated soil was sampled and analyzed for pH, N and P contents.

Results: Compared with the control, incubation of organic residues increased soil pH, however, changes in soil pH varied in the soils. Poultry manure was more effective in reducing soil acidity in Majeroku (Abruptic Tropaqualf) and Itagunmodi (Rhodic Paleutult) soils than in Egbeda (Oxic Paleustult) soil. Mean changes in available P with incubation of tithonia compost were 1.2, 1.65 and 3.07 mg kg-1 in Egbeda, Itagunmodi and Majeroku soils respectively while with the incubation of poultry manure were 3.79, 1.92 and 6.06 mg kg-1 in the three soils respectively. Incubation of the residues reduced available N except for poultry manure which enhanced N availability in Majeroku soil.

Conclusion: Nutrient release pattern of the residues varied with soil types and are dependent on soil characteristics that may influence nutrient use efficiency by crops. Poultry manure was more effective in increasing P availability in the soils than tithonia compost.

Open Access Original Research Article

Inoculated Soybean Yields Response to Nitrogen and Phosphorus Application

Austin T. Phiri, Esther Mwende Muindi, Jacob Omondi Omollo, Rebecca Yegon, Daniel Kausiwa

International Journal of Plant & Soil Science, Page 1-7
DOI: 10.9734/IJPSS/2016/24905

Inherent low soil nitrogen (N) and phosphorus (P) is one of the major hindrances of increased soybean productivity in Malawian soils. Although, inoculation of legumes with rhizobia, has been advocated for decades as a way of boosting leguminous crops’ productivity through biological nitrogen fixation (BNF), the effectiveness of this strategy, has been low. An experiment was carried out to investigate the effect of the application of small doses of N and P to inoculated soybean. It was laid out in a complete block design (CBD) replicated three times and the treatments included: 1. Soybean only, 2. Inoculated soybean, 3. Inoculated soybean + 30 kg N ha-1, 4. Inoculated soybean + 30 kg N ha-1 + 25 kg P ha-1, 5. Inoculated soybean + 30 kg N ha-1 + 35 kg P ha-1. The soybean in all treatment plots except for treatment 1 was inoculated with 30 kg N ha-1 applied as urea to treatment plots 3, 4 and 5. Phosphorus as TSP was applied to treatment 4 and 5 at the rate of 25 and 35 kg P ha-1. Data collected included; selected soil physical and chemical properties, biomass and pod yields. Data obtained were subjected to Analysis of Variance (ANOVA) using the GenStat statistical package and treatment effects tested for significance using the F-test at 5% level of significance. Means were separated using the least significant difference (P<0.05). Results indicate that inoculating soybean with rhizobia and inoculating soybean with rhizobia plus applying 30 kg N ha-1 did not significantly increase biomass yields. However, inoculating soybean plus the combined application of 30 kg N ha-1 and, 25 kg P ha-1 or / and 35 kg P ha-1 increased the soybean biomass yields by 54% and 70% respectively above control. The lack of significant response when N was applied without P points to the significant role played by phosphorus in root development and energy transfer processes within the plant. Effective nodulation, however, was significantly higher (p<0.05) above the control where inoculation was combined with the application of 30 kg N ha-1 and 35 kg P ha-1, hence underlining the role played by phosphorus in nodule development and the role of starter N in soils low in N.